Electrical plug and socket



Dec. 14, 1948. L. WEINER ET A; 2,456,548

ELECTRICAL PLUG AND SOCKET- Filed March 25, 1946 a Sheets-Sheet 1 '7 .f. Z5 475i? Z0 I Leon VVez'ner 72'9 ,B.[.,B@ZZ

14, 1943'- L. WEINER ET-AL I 2,456,548

ELECTRICAL PLUG AND SOCKET Filed March 25, 1946 I 3 Sheets-Sheet 2 Z6071 Wei er 5.1.,BeZZ

Patented Dec. 14, 1948 UNITED. STATES OF F I C E 2,456,5fl' ELEoTmoAL PLUGAND, sooner been Weinerand Bernard I. Bell, Houston, Tex;

Application March .25, 1946,; Serial .Nor- 656,801.

This invention relates to an improved electrical plug for a socket .and moreparticularly for an electric cord plug which .is locked, in engagement with the socket.

It is an object of this invention to provide an electric plug which is provided with means for iasteningthev plug to a socket.

Another object of this invention is to provide a plu which is providedwith means, independent of theccontact prongs, for locking the plug to a socket and means for. disengagingthe, plug from the socket.

Stillanother object of the invention is to provide a plug which is adapted torberemovablysecured to, a socket and. WhlCh.COI1t2.inS spring means for disengagingthe plugfrom the socket plug to the socket and a,ring;1for holding th'e locking means in the locked position A still further object of this invention is to provide a socket plate particularlyadapted to the plug which may be locked to, the socket;

Yet another object of this invention is to ,provide an adapter whereby this lockableplug; may be used with a conventionalsocket and plate.

Still another object of this invention is'to provide a socket for use with the lockingplug where.- in the socket is so constructed-- that the-contact terminals are concealed. within the socket" by plates which are spring pressed to a concealing positionand are opened to-permitjaccessto the terminals by the-insertion of :the lockable plug into the socket.

To the foregoing objects; andpthers'which may hereinafter more fully appear,- the'invention' con,- sists of the novel'construction, combinationnnd arrangement of parts, as'will be more specifically referred to and 'illustratedirr the accompanying drawings, but it is'to'be-understood that changes, variations, and modifications mayybe resorted to which fall within the scope of the invention as claimed.

In the drawings:

Figure 1 is aside elevation of filliIHPI'OVBd'BlBCr tric plug constructed according to. anembodiment of our invention,

Figure 2 is an end'view. of the-plug,

2 Claims. (Cl: 173-461) 2. Figure"3"is a section taken on the line 3-3 of Figure 1-, Y

Figure 4 is a fragmentary detailsection taken on the line*4-4j0fFigure 3,

Figure '5Lis'a detail section taken on the line 5;5"ofFlgure 1;.

Figure 6; is atop plan of a socket cover adapted to the plug,

Figure? is asecti'on taken on the line 1-4 of Figure 6,

Figure 8 is a section taken on the line 8-43 of Eigurefi;

Figure"9 is atop plan-view of an adapter for the plug 'tobe used with a conventional socket,

Figure-10 is a section taken on line Ill-ID of Figure-9;

Figure 11 is-a plan view of a socket particularly adapted-1:0 this plug,

Figure 12 is a section taken on the line i2-i2 o-f-Figure- 11,

Figure 1 3 is a section taken on the line l3l3 of l i'gure 12,-

Figure-14 isa-section taken on the line M-M of Figure '12, and.

Figure-151sa' sectiontaken on the line l5l5 of Figure 12.

Reterring to the=-drawings, the numeral 20 designates generally anele'ctrical plug constructed according to an embodiment of our invention. Thebodyof the plug'consists of two half sections-"21 and' fiz held together by screws 23 or other suitable fastening means. The body is made ot' ru'bber orother non-conducting material. One of the' sectionsas 2|, isacover and the other parts are secured into the other section 22.

.a pair of m-etal prongs 24 are fixed into the section -22and extend therefrom in a conventional manner. The wires 25 and 26 of the cord 2'! attach to the-prongs 2 t Withinthe plug 20 by screws-231L01 other conventional means of attachment;

The bod y sections Zi'= and-22 are formed with inside wall s 28- forming a cylindrical guideor channel-28. The head 3 0of the piston or plunger 3;liis:slidab'l'e. in the guide 29, and the plunger 3| extendsthroughthenend of the plug 20: between the-prongs;- 24 Aiplugtz, having limited sliding mevementinthe-guide 2B is adapted to close the inner endioflthe guide 29. A spring 33 which projects into the plunger 3| is held between the plunger 3l .an-d theplug, 32 and constantly urges the plunger-Iiloutwardly and plug 32 inwardly. Onearin 4i! or each of a pair of V-shaped bell cranks;3A,rockably,secured to the body section 22, bearsgagainst.the-rear side of .the plug 32. to

3 prevent the plug 32 from sliding out of th guide 29.

A pair of pivotal locking levers 35 are pivoted within the section 22, near the outer end of the body 22, extend forwardly and project from the inner end outwardly from the prongs 24. The levers 35 are formed at their projecting ends with an inwardly opening hook 36 and an inwardly extending chamfer 37. The other ends of the levers 35 extends outwardly from the outer end of the body 22 and lie substantially parallel to the shank 38 of the body 22, spaced from the shank 38 to form handles 39 which may be pressed apart and open the hooks 36.

ings 52 are provided with a rim 53 along the The other arm 4! of the bell crank 34 is pro vided with a lug 42 which engages the outer side of the levers 35,so that the force of the spring 33 is transmitted through the plug 32 through the bell crank 34 to hold the levers 35 inwardly and the hooks 36 in the locking or engaging position.

An inwardly projecting cam lug 42a or rounded projection is provided on the forwardly extending arm of the lever 35 for opening the hooks 36. A wedge-shaped cam or sleeve 43 is fixed to the cord 21 and is engageable with the lugs 42a. The sleeve 43 is slidably secured within the body 22 by projecting guide lugs 44 which are slidable in the slot 45 of the guide plate 46, which plate 46 is fixed to the plug 32. M I

A locking ring 4! is rotatable about the shank 38 and is formed with opposed cutout sections 48 to provide for selectively looking or unlocking the handles 39. The ring 41 fits between the shank 38 and handles 39 so that the handles 39 can not be pressed inwardly until the ring 4'! is turned so the openings 43 align with the handles 39 and the recesses 49 in the shank 38.

In the use and operation of this plug '26, the plug is simply pressed into a socket adapted to receive this plug until the hooks 36 engage the socket plate. By pressing the plug 26 into place the plunger 35 is forced against the tension of spring 33, which tension is transmitted to the levers 35 to hold the hooks engaged. The plug may be locked in engaged position by rotating the ring so that the handles 39 cannot be pressed inwardly. The plug 20, when unlocked, may be removed in two ways. First, by pressing the lever handles 39 together the hooks 36 are disengaged and the plunger 3|, bearing against the center of the socket plate, urges the plug .20 out of the socket. Secondly, a pull on the cord 27, moves the wedge-shaped cam 43 rearwardly. The projections 42a on the levers 35 are forced apart by the cam until the hooks 36 are disengaged from the socket plate and the plunger 3| urges the plug out of the socket. The cam 43 is urged back into position when the hooks are spread apart upon reinsertion of the plug into the socket, at which time the outward motion of the hook arms 35 is transmitted through the bell crank arms 4! by means of the lugs 42, so that the fiat ends of the arms 4| press upward against sliding plug 32, moving guide plate 46 upward so that the end of the slot in it engages the lug 44 on the sliding wedge 43, putting sliding wedge 43 back to normal position and allowing hook arms 35 to (.lose to normal locking position. When hook arms 35 are in normal locking position, bell cranks 34 move back and allow sliding plug 32 to slide down under pressure of the spring 33. The slotted plate 46 is then moved into a position leaving room in the slot for the wedge inner edge thereof and the forward side of the rib 53 is beveled to urge the hooks 36 apart as they are pressed inwardly. The hooks 36 then engage the rear straight edge of the rib 53 to lock the plug 26 to the socket plate 50.

I In Figures 9 and 10 we have shown an adapter plug for using the plug 20 with a conventional socket and socket plate installation. The adapter plugfifl is formed with an annular two section body 61 held together by a bolt 62. Prongs 63, fixed into the body 6! are adapted to be inserted into a standard socket. Within the body 6| the prongs 63 terminate in spring metal terminals 64. The front surface of the adapter 60 is provided with openings 65, through which prongs 24 are inserted and engage in the terminals 64. The edge of the front surface is formed with notches 66 having inner beveled ribs 61, with which the hooks 36 are engaged. A central wall 68 is provided within the adapter 66 to reinforce the front surface so it may withstand the force of the spring pressed plunger 31.

In Figures 11 to 15, we have illustrated a socket which is, especially adapted to this plug 26 and in which the terminals are concealed or covered and are exposed only at the time a plug is inserted, at which time the plug 20 actuates means for exposing the terminals.

. The socket 10 is formed with a substantially rectangular hollow body H. A pair of spring terminals 12 are fixed to the rear end of the body H and the electric wires are fastened to the terminals 12 by screws 13. The front wall 14 of the body H is formed with prong openings 15, ribbed hook openings 16, and a large central circular opening 11. Two opposite inner side walls are formed with a guide block l8. The front of the block 18 is formed with a centrally located recess 19 forming a ledge 80, and a rearwardly extending slot or groove Bl. Pivotally secured between the otherv two opposite side walls are a pair of closure plates 82 which cover the terminals 12 in their closedposition. An extension 83 of one edge of each plate '82 is pivotally supported byextending into bores 84 in the walls, and centrally of each plate 82 extending outwardly from .the extended edges, a U-shaped lever 85 is fixed for rocking the plate 82 about the pivot 83.

A hearing plate 86 is fixed to the ledges 86 between the blocks 18. A circular plunger head or button 81 is supported in the opening 1! by the arms 88 of a U-shaped supporting member. The bight 89 of the U-shaped member is below the plate 86 and the arms 88 extend forwardly aroundthe plate 86 to support the button 81. A U-shaped closure actuating member 90 is fixed to the bight 89 of the supporting member and the arms of the member 90 extend to engage the lever arms 85 of the closures 62. The member '90 is slidably supported in the grooves 8| and the arms of the member 90 are formed with inwardly and forwardly extending notches 9|.

The levers 85 engage in the notches 9| for actuating the closure plates 82. The spring 92, between the bearing plate 86 and the button 81 constantly urged the button 81 outwardly and the plates 82 closed.

The normal position of the socket is illustrated in Figures 11 to 15, in which the button 81 is normally in the opening 11 and the closure plates 82 are closed over the terminals 12.

When the plug 20 is pressed into engagement with the socket 10, the plunger 3| presses the button 81 inwardly as the prongs 24 are inserted in the openings 15. At the button 81 moves inwardly the actuating member 90 presses inwardly on the levers 85 thereby opening the closure plates 82 before the prongs 24 are fully within the socket, thus permitting further travel of the prongs 24 to engage the prongs 24 with the terminals 12. Upon complete insertion of the plug 20 the hooks 36 will engage the ribbed openings 16 to hold the plug 20 in engagement with the socket 1D. The removal of the plug 20 is the same as stated before.

The exact configuration illustrated is regarded as the optimum, but some of the desirable results inherent in this disclosure may be obtained by various slight modifications including some departure from the exact configuration shown, and it is therefore requested that the scope of the invention should be regarded as limited only by the terms of the claims.

Having thus described our invention what we claim is:

1. An improved electric connecting plug comprising a hollow body, conducting prongs extending from an end of said body, a pair of elongated levers pivoted intermediate their length in said body extending therefrom adjacent said prongs at one end and extending outwardly from said body at the other end, hooks on said levers at said one end, a pair of bellcranks rockable in said body, a plunger slidable in said body, a plug slidable in said body, a compressible spring between said plunger and said plug, one arm of each bellcrank abutting an end of said plug, the other arm of said bellcranks engaging said levers for biasing said levers in opposite directions, a cam slidable in said housing fixed on an electric cord extending therein engageable with said levers for rocking said levers against the spring tension for releasing the plug from hooked engagement with a correlated socket.

2. An improved electric plug for hook engagement with a correlated socket comprising a hollow body, conducting prongs extending from said body, a pair of levers pivoted in said body, one arm of each lever extending from said body adjacent said prongs, a hook on said one arm for engagement with said socket, the other arm of said levers extending from said body constituting handles for rocking said levers manually, a plunger slidable in said body and extensible thereform for urging said plug out of engagement with said socket, a sliding member slidable in said body, a spring between said member and said plunger, a second pair of levers rockable in said body, one arm of each of said latter levers engageable with said sliding member, the other arm of said latter levers engageable with said first levers biasing said hooks to opposed hooked position, in an electric cord in said plug connected to said prongs, a slidable cam member on said cord engageable with said first levers for rocking said first levers against the spring tension upon tensioning said cord whereby said plunger will urge said plug from engagement with said socket.

LEON WEINER. BERNARD I. BELL.

' REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,159,207 Gauthier Nov. 2, 1915 1,526,265 Bergman Feb. 10, 1925 1,579,865 Hubbell Apr. 6, 1926 1,899,360 Rondebush Feb. 28, 1933 1,946,786 Featherston Feb. 13, 1934 2,201,919 Prendergast May 21, 1940 2,235,020 Jones Mar. 18, 1941 2,394,618 Kunasch Feb. 12, 1946 FOREIGN PATENTS Number Country Date 409,155 Great Britain Apr. 26, 1934 571,528 Germany Mar. 2, 1933 

